﻿/************************************************************************

   Extended Silverlight Toolkit

   Copyright (C) 2010-2012 Xceed Software Inc.

   This program is provided to you under the terms of the Microsoft Public
   License (Ms-PL) as published at http://extendedsilverlight.codeplex.com/license

   Please purchase a commercial version of this toolkit if you are using
   it in a commercial product. The commercial versions support the project,
   and also include more features for each control, priority support,
   source code, updates, removed watermark, and a proprietary license.

   Visit http://xceed.com and follow @datagrid on Twitter.

  **********************************************************************/

using System;
using System.Windows;
using Xceed.Silverlight.Data;

namespace Xceed.Silverlight.ListBox
{
  internal class BringContainerCompletelyIntoViewNavigationAction : PanelNavigationActionBase
  {
    internal BringContainerCompletelyIntoViewNavigationAction( DataPath targetDataPath, PanelBase panel, NavigationInfo navigationInfo )
      : base( panel, navigationInfo )
    {
      this.TargetDataPath = targetDataPath;
    }

    internal DataPath TargetDataPath
    { 
      get; 
      private set; 
    }

    internal override double CalculateTargetScrollIndex()
    {
      ContainerDescription containerDescription = this.Panel.LayoutManager.ContainerDescriptions[ this.TargetDataPath ];

      if( containerDescription == null )
        return -1;

      return ( this.NavigationInfo.IsForwardScrolling ) ? containerDescription.ScrollIndexAsBottomItem : containerDescription.ScrollIndexAsTopItem;
    }
  }
}
